Effect of ambient concentration of carbon monoxide (Co) on the in-vehicle concentration of carbon monoxide in chennai, india

Abstract

In this study, ambient concentration of Carbon monoxide (CO) was monitored at two locations, a signalized traffic intersection and at one kilometer away from the intersection in Chennai. The maximum CO concentration was found to be 38.82 mg/m3 and 1.15 mg/m3 at signalized traffic intersection and one kilometer away from the intersection, respectively. The 1 h average in-vehicle carbon monoxide concentration in cars during Air Conditioner (A/C)-ON recirculation mode, A/C-ON fresh air mode and windows open mode are 2.4 mg/m3, 4 mg/m3 and 5.7 mg/m3, respectively. The dilution rates of CO in these modes were found to be 0.14 mg/m3/min, 0.51 mg/m3/min and 1.71 mg/m3/min, respectively. The Root Mean Square Error (RMSE) for A/C recirculation, A/C fresh air, windows open modes in car and windows open in bus were 2.06, 3.27, 0.79 and 1.82, respectively. For short trips, A/C-on recirculation mode was found to be suitable and continuous use of A/C in longer trips led to accumulation of CO. It is advisable to switch to either A/C on Fresh air mode or windows open mode during longer trips to prevent accumulation of in-vehicle CO.